Al-Aḥsāʾī, founder of the heterodox Shīʿite Muslim Shaykhī sect of Iran. After spending his early years studying the Islāmic religion and traveling widely in Persia and the Middle East, al-Aḥsāʾī in 1808 settled in Yazd, Persia, where he taught religion. His interpretation of the Shīʿite faith (one

Martti Ahtisaari, Finnish politician and noted mediator who was president of Finland (1994–2000). In 2008 he was awarded the Nobel Prize for Peace for his efforts to resolve international conflicts. Born in Viipuri, Finland, Ahtisaari was displaced along with the rest of his family when the city

Oceanic art and architecture: Polynesia: …with a raised platform (ahu) across one end. A row of upright stone slabs along the ahu were backrests for the gods, while other stones indicated the places of human officiants. The grounds went through various phases of development in the island groups and were the Polynesians’ most conspicuous…

Avocado, fruit of Persea americana of the family Lauraceae, a tree native to the Western Hemisphere from Mexico south to the Andean regions. Avocado fruits have greenish or yellowish flesh with a buttery consistency and a rich, nutty flavour. They are often eaten in salads, and in many parts of the

Ahuachapán, city, western El Salvador, on the small Molino River (with a hydroelectric station) at the foot of La Lagunita Volcano. Originally called Güeciapam by the Indians, it was renamed Agüecha before becoming the town (1823) and the city (1862) of Ahuachapán. A manufacturing and distributing

bald cypress: The closely related Montezuma, or Mexican, cypress (T. mucronatum) is native to the southwestern U.S., Mexico, and Guatemala. It is generally considered to be a separate species and is distinguished from the bald cypress by its shorter, persistent leaves and larger cones. It rarely produces knees.

Ahuitzotl, eighth king of the Aztecs, under whose reign (1486–1503) the Aztec empire reached its greatest extent. The aggressive Ahuitzotl succeeded his brother, Tizoc, to the throne. He proved an effective warrior, conquering tribes as far south as present-day Guatemala and in territory along the

Zoroastrianism: Cosmology: …with the help of the Ahuna Vairya prayer (the most sacred Zoroastrian prayer), and he lay prostrate for another period of 3,000 years, the second in a total of four. He was then stirred up by the prostitute (Primal Woman) and went back to the attack, this time in the…

Hawaiian: …basic unit of land, the ahupuaa, usually extended from the shore to the mountaintop, with rights in the adjoining sea waters, so that the occupants had the means of supplying all their wants—the sea for fish; the littoral for coconuts; the valley for taro, their principal food; the lower slopes…

Asura, (Sanskrit: “divine”) in Hindu mythology, class of beings defined by their opposition to the devas or suras (gods). The term asura appears first in the Vedas, a collection of poems and hymns composed 1500–1200 bce, and refers to a human or divine leader. Its plural form gradually predominated

Ahura Mazdā, (Avestan: “Wise Lord”) supreme god in ancient Iranian religion, especially Zoroastrianism, the religious system of the Iranian prophet Zarathustra (c. 6th century bce; Greek name Zoroaster). Ahura Mazdā was worshipped by the Persian king Darius I (reigned 522–486 bce) and his

Ahvāz, city, capital of Khūzestān province, southwestern Iran. Ahvāz is situated on both banks of the Kārūn River where it crosses a low range of sandstone hills. The town has been identified with Achaemenid Tareiana, a river crossing on the royal road connecting Susa, Persepolis, and Pasargadae.

Åland Islands, archipelago constituting Åland (Ahvenanmaa) autonomous territory, southwestern Finland. The islands lie at the entrance to the Gulf of Bothnia, 25 miles (40 km) east of the Swedish coast, at the eastern edge of the Åland Sea. The archipelago has a land area of 599 square miles (1,551

Ḥāl, (Arabic: “condition”, ) in Ṣūfī Muslim mystical terminology, a spiritual state of mind that comes to the Ṣūfī from time to time during his journey toward God. The aḥwāl are graces of God that cannot be acquired or retained through an individual’s own efforts. When the soul is purified of its

Ahvāz, city, capital of Khūzestān province, southwestern Iran. Ahvāz is situated on both banks of the Kārūn River where it crosses a low range of sandstone hills. The town has been identified with Achaemenid Tareiana, a river crossing on the royal road connecting Susa, Persepolis, and Pasargadae.

sloth: Three-toed sloths:
The three-toed sloth (family Bradypodidae) is also called the ai in Latin America because of the high-pitched cry it produces when agitated. All four species belong to the same genus, Bradypus, and the coloration of their short facial hair bestows them with a…

Sweetfish, delicately flavoured marine fish that migrates upstream to spawn in clear waters. It is found in East Asia and is of the family Osmeridae. The sweetfish is light yellow or olive-coloured, about 30 cm (1 foot) long, and similar to a small trout in appearance. It is distinguished by a

Ai, ancient Canaanite town destroyed by the Israelites under their leader Joshua (Joshua 7–8). Biblical references agree in locating Ai (Hebrew: ha-ʿAy, “The Ruin”) just east of Bethel (modern Baytīn in the West Bank). This would make it identical with the large early Bronze Age site now called

human nutrition: Dietary Reference Intakes: …scientific evidence, another parameter, the Adequate Intake (AI), is given, based on estimates of intake levels of healthy populations. Lastly, the Tolerable Upper Intake Level (UL) is the highest level of a daily nutrient intake that will most likely present no risk of adverse health effects in almost all individuals…

Artificial intelligence (AI), the ability of a digital computer or computer-controlled robot to perform tasks commonly associated with intelligent beings. The term is frequently applied to the project of developing systems endowed with the intellectual processes characteristic of humans, such as

Amnesty International (AI), international nongovernmental organization (NGO) founded in London on May 28, 1961, that seeks to publicize violations by governments and other entities of rights recognized in the Universal Declaration of Human Rights (1948), especially freedom of speech and of

Ai Qing, Chinese poet whose free verse was influential in the development of xinshi (“new poetry”). The son of a well-to-do landowner, Ai Qing was encouraged to learn Western languages. He studied painting in Paris from 1928 to 1932, and he developed an appreciation for Western literature.

Artificial intelligence programming language, a computer language developed expressly for implementing artificial intelligence (AI) research. In the course of their work on the Logic Theorist and GPS, two early AI programs, Allen Newell and J. Clifford Shaw of the Rand Corporation and Herbert Simon

Ai Qing, Chinese poet whose free verse was influential in the development of xinshi (“new poetry”). The son of a well-to-do landowner, Ai Qing was encouraged to learn Western languages. He studied painting in Paris from 1928 to 1932, and he developed an appreciation for Western literature.

Ai Weiwei, Chinese artist and activist who produced a multifaceted array of creative work, including sculptural installations, architectural projects, photographs, and videos. While Ai’s art was lauded internationally, the frequently provocative and subversive dimension of his art, as well as his

Ai Weiwei, Chinese artist and activist who produced a multifaceted array of creative work, including sculptural installations, architectural projects, photographs, and videos. While Ai’s art was lauded internationally, the frequently provocative and subversive dimension of his art, as well as his

Artificial intelligence, situated approach, method of achieving artificial intelligence (AI). Traditional AI has by and large attempted to build disembodied intelligences whose only interaction with the world has been indirect (CYC, for example). Nouvelle AI, on the other hand, attempts to build

construction: Emergence of design professionals: …both in London, and the American Institute of Architects (1857). Official government licensing of architects and engineers, a goal of these societies, was not realized until much later, beginning with the Illinois Architects Act of 1897. Concurrent with the rise of professionalism was the development of government regulation, which took…

aerospace industry: Character of the industry: …industry are represented through the Aerospace Industries Association of America (AIA), an aerospace-industry-funded organization whose membership consists of the major companies in the field. The AIA provides a forum for technical and policy issues concerning the industry and serves as a lobbying agent for the common interests of its members.…

Ugo Foscolo: …to Napoleon in his tragedy Aiace (first performed 1811; “Ajax”) again brought suspicion on him; in 1812 he moved to Florence, where he wrote another tragedy, Ricciarda, and most of his highly acclaimed unfinished poem, Le grazie (published in fragments 1803 and 1818, in full 1822; “The Graces”). In 1813…

All India Dravidian Progressive Federation, Regional political party of India, principally in Tamil Nadu state. It was formed in 1972 by veteran movie-actor-turned-politician Maruthur Gopala Ramachandran (popularly known as MGR), who broke away from the Dravidian Progressive Federation (Dravida

Ajax, in Greek legend, son of Telamon, king of Salamis, described in the Iliad as being of great stature and colossal frame, second only to the Greek hero Achilles in strength and bravery. He engaged Hector (the chief Trojan warrior) in single combat and later, with the aid of the goddess Athena,

Ajax, in Greek legend, son of Oileus, king of Locris; he was said to be boastful, arrogant, and quarrelsome. For his crime of dragging King Priam’s daughter Cassandra from the statue of the goddess Athena and violating her, he barely escaped being stoned to death by his Greek allies. Odysseus knew

robot: Robot toys: … introduced a doglike robot named AIBO, with two dozen motors to activate its legs, head, and tail, two microphones, and a colour camera all coordinated by a powerful microprocessor. More lifelike than anything before, AIBOs chased coloured balls and learned to recognize their owners and to explore and adapt. Although…

Jean Aicard, French poet, novelist, and dramatist, best known for his poems of the Provence region. As a young man Aicard studied law but abandoned it to devote himself to literature. His first book of poetry, Jeunes croyances (1867; “Beliefs of a Youth”), showed the influence of the Romantic poet

Jean Aicard, French poet, novelist, and dramatist, best known for his poems of the Provence region. As a young man Aicard studied law but abandoned it to devote himself to literature. His first book of poetry, Jeunes croyances (1867; “Beliefs of a Youth”), showed the influence of the Romantic poet

Aichbühl, site of a Middle Neolithic settlement (end of the 3rd millennium bc) on the shores of Lake Feder (Federsee) in southeastern Baden-Württemberg Land (state), southwestern Germany. Foundations of 25 rectangular buildings arranged in an irregular row along the shoreline were uncovered in the

industrial design: American hegemony and challenges from abroad: …founders was the typeface designer Otl Aicher, a corporate-branding specialist, noted author of graphic standards manuals for his clients, and designer whose clients included Lufthansa and Munich’s transportation authority. Aicher’s contributions to the development of postwar graphic design and corporate identity may have even surpassed those of the legendary Herbert…

Aichi, ken (prefecture), central Honshu, Japan, on the Pacific coast. Nagoya, at the head of Ise Bay, is the prefectural capital. More than half of Aichi’s area lies within the Nōbi Plain and two smaller plains to the east. The northwestern border with Gifu prefecture is formed by the Kiso River,

biodiversity loss: Solutions to biodiversity loss: …20 biodiversity goals, called the Aichi Biodiversity Targets, was unveiled at the CBD meeting held in Nagoya, Japan, in October 2010. The purpose of the list was to make issues of biodiversity mainstream in both economic markets and society at large and to increase biodiversity protection by 2020. Since 2010,…

Gregor Aichinger, German composer of religious music during the stylistic transition from the late Renaissance to early Baroque. Aichinger took holy orders and became organist to the family of Jakob Fugger at Augsburg from 1584. He visited Italy in 1584–87 and again in 1598–1600. His music is

Ilse Aichinger, Austrian poet and prose writer whose work, often surreal and presented in the form of parables, reflects her preoccupation with the Nazi persecution of the Jews during World War II. Aichinger’s education was interrupted by World War II when, because she was half Jewish, she was

Aid, a tax levied in medieval Europe, paid by persons or communities to someone in authority. Aids could be demanded by the crown from its subjects, by a feudal lord from his vassals, or by the lord of a manor from the inhabitants of his domain. A feudal lord could ask his vassals for an aid

Buoy, floating object anchored at a definite location to guide or warn mariners, to mark positions of submerged objects, or to moor vessels in lieu of anchoring. Two international buoyage systems are used to mark channels and submerged dangers. In both systems, buoys of standardized colours and

Social welfare program, any of a variety of governmental programs designed to protect citizens from the economic risks and insecurities of life. The most common types of programs provide benefits to the elderly or retired, the sick or invalid, dependent survivors, mothers, the unemployed, the

Dominique Pire: In 1949 he founded Aid to Displaced Persons, which sought to guarantee moral and material aid to refugees, regardless of their nationality or religion, and soon had branches throughout Europe. Between 1950 and 1954 Pire founded four “homes of welcome” in Belgium for aged refugees. Seven European “villages” were…

Foreign aid, the international transfer of capital, goods, or services from a country or international organization for the benefit of the recipient country or its population. Aid can be economic, military, or emergency humanitarian (e.g., aid given following natural disasters). Foreign aid can

Giuseppe Verdi: The later middle years: …libretto exactly to his needs, Aida. Verdi wrote a detailed scenario—much simpler than those of the previous two operas—employing Antonio Ghislanzoni, a competent poet, to turn it into verse, the metres of which were often dictated by the composer. Commissioned by the khedive of Egypt to celebrate the opening of…

Setsuko Hara, (Masae Aida), Japanese actress (born June 17, 1920, Yokohama, Japan—died Sept. 5, 2015, Kamakura, Japan), won acclaim and adulation for her subtle and moving portrayals of women who bowed to the demands of duty, subsuming their own desires for independence. She was best known for her

Aidan, king of the Scottish kingdom of Dalriada. He was the son of Gabran, king of Dalriada. Aidan was inaugurated as king at Iona by St. Columba. He refused to allow his kingdom to remain dependent on the Irish Dalriada; but, coming into collision with his southern neighbours, he led a large force

Saint Aidan, apostle of Northumbria, monastic founder, first bishop of Lindisfarne, or Holy Island, off the coast of Northumberland. Aidan was a monk at Iona, an island of the Inner Hebrides in Scotland, when King Oswald of Northumbria requested that he be made bishop of the newly converted

France: Tax reform: …internal and external; and the aides, or excise taxes, levied on the sale of items as diverse as wine, tobacco, and iron. All the indirect taxes were extremely unpopular and had much to do with the state’s inability to rally the rural masses to its side in 1789. In the…

Aide-de-camp, (French: “camp assistant”), an officer on the personal staff of a general, admiral, or other high-ranking commander who acts as his confidential secretary in routine matters. On Napoleon’s staff such officers were frequently of high military qualifications and acted both as his “eyes”

Hades, in Greek mythology, god of the underworld. Hades was a son of the Titans Cronus and Rhea, and brother of the deities Zeus, Poseidon, Demeter, Hera, and Hestia. After Cronus was overthrown by his sons, his kingdom was divided among them, and the underworld fell by lot to Hades. There he ruled

Zhu Wen: …on the throne as the Aidi emperor and was forced to abdicate to Zhu in 907. Zhu then proclaimed himself first emperor of the Hou Liang dynasty. Five years later he was murdered by his own eldest son, who succeeded him on the throne.

China: From Chengdi to Wang Mang: …reigns of Chengdi (33–7 bce), Aidi (7–1 bce), and Pingdi (1 bce–6 ce) the conduct of state affairs and the atmosphere of the court were subject to the weakness or youth of the emperors, the lack of an heir to succeed Chengdi, and the rivalries between four families of imperial…

Ama Ata Aidoo, Ghanaian writer whose work, written in English, emphasized the paradoxical position of the modern African woman. Aidoo began to write seriously while an honours student at the University of Ghana (B.A., 1964). She won early recognition with a problem play, The Dilemma of a Ghost

Ama Ata Aidoo, Ghanaian writer whose work, written in English, emphasized the paradoxical position of the modern African woman. Aidoo began to write seriously while an honours student at the University of Ghana (B.A., 1964). She won early recognition with a problem play, The Dilemma of a Ghost

epic: The heroic life: As long as the goddesses Aidos (a personification of the sense of shame) and Nemesis (a personification of divine retribution) stay with humankind, however, helping people observe their moira without committing excesses, one can still gain riches, merits, and glory by the sweat of one’s brow. Only if one knows…

AIDS, transmissible disease of the immune system caused by the human immunodeficiency virus (HIV). HIV is a lentivirus (literally meaning “slow virus”; a member of the retrovirus family) that slowly attacks and destroys the immune system, the body’s defense against infection, leaving an individual

ACT UP, international organization founded in the United States in 1987 to bring attention to the AIDS epidemic. It was the first group officially created to do so. ACT UP has dozens of chapters in the United States and around the world whose purpose is to find a cure for AIDS, while at the same

AIDS: Social, legal, and cultural aspects: …than 48,000 panels of the AIDS Memorial Quilt, which has been displayed worldwide both to raise funds and to emphasize the human dimension of the tragedy. The United Nations designated December 1 as World AIDS Day.

human sexual activity: Acquired immunodeficiency syndrome: …to as AIDS-related complex (ARC) and include fever, rashes, weight loss, and wasting. Opportunistic infections such as Pneumocystis carinii pneumonia, neoplasms such as Kaposi’s sarcoma, and central nervous system dysfunction are also common complications. The patient eventually dies, unable to mount an immunologic defense against the constant onslaught of…

Institutional economics, school of economics that flourished in the United States during the 1920s and ’30s. It viewed the evolution of economic institutions as part of the broader process of cultural development. American economist and social scientist Thorstein Veblen laid the foundation for

Henry Paulson: …that enabled the insurance corporation American International Group (AIG), Inc., to avoid bankruptcy. Additionally, Paulson cooperated with Bush, Bernanke, and others to draft the Emergency Economic Stabilization Act of 2008 (EESA), a bailout of the U.S. financial system made necessary by the growing credit crisis; the EESA was signed into…

Edessa: …Edessa was the location of Aigai, the first capital of ancient Macedonia, was seriously challenged by the discovery in 1977 of royal tombs of Macedonian leaders at Verghina, southeast of Véroia, including one identified as that of Philip II. In Roman times Edessa was a stop on the Via Egnatia…

Aegean Sea, an arm of the Mediterranean Sea, located between the Greek peninsula on the west and Asia Minor on the east. About 380 miles (612 km) long and 186 miles (299 km) wide, it has a total area of some 83,000 square miles (215,000 square km). The Aegean is connected through the straits of the

Windhoek, town, capital of Namibia, located roughly in the centre of the country. It lies at an elevation of 5,428 feet (1,654 metres) and is about 400 miles (650 km) north of the Orange River and 760 miles (1,225 km) north of Cape Town, South Africa. The town is surrounded by dry, arid country,

Edessa: …Edessa was the location of Aigai, the first capital of ancient Macedonia, was seriously challenged by the discovery in 1977 of royal tombs of Macedonian leaders at Verghina, southeast of Véroia, including one identified as that of Philip II. In Roman times Edessa was a stop on the Via Egnatia…

Saronikós Gulf, gulf of the Aegean Sea between Ákra (cape) Soúnion of the Attica (Modern Greek: Attikí) peninsula and Ákra Skíllaion of the Argolís peninsula of the Greek Peloponnese (Pelopónnisos). A maximum of 50 miles (80 km) long northwest-southeast and about 30 miles wide, it is linked on the

Edmond Rostand: …that is still remembered is L’Aiglon (1900). This highly emotional patriotic tragedy in six acts centres on the Duke of Reichstadt, who never ruled but died of tuberculosis as a virtual prisoner in Austria. Rostand always took pains to write fine parts for his stars, and L’Aiglon afforded Sarah Bernhardt…

Ladislas Aigner, (“Lucien”), Hungarian-born photojournalist whose use of the then new 35-mm Leica camera made him one of the pioneers in candid news photography in the 1930s and allowed him to capture such famous images as Albert Einstein standing before a blackboard and looking slightly rumpled

Ladislas Aigner, (“Lucien”), Hungarian-born photojournalist whose use of the then new 35-mm Leica camera made him one of the pioneers in candid news photography in the 1930s and allowed him to capture such famous images as Albert Einstein standing before a blackboard and looking slightly rumpled

Aigrette, tuft of long, white heron (usually egret) plumes used as a decorative headdress, or any other ornament resembling such a headdress. Such plumes were highly prized as ornaments in Middle Eastern ceremonial dress. Jeweled aigrettes, at first made in the form of a tuft of plumes, became an

Aigues-Mortes, town, Gard département, Occitanie région, southeastern France, southwest of Nîmes, on the Canal du Rhône à Sète, with its own 3.5-mile (6-km) canal to the Gulf of Lion. Its name comes from aquae mortuae, the “dead waters” of the surrounding saline delta marshland. Built by Louis IX

Emmanuel-Armand de Richelieu, duke d’Aiguillon, French statesman, whose career illustrates the difficulties of the central government of the ancien régime in dealing with the provincial Parlements and estates, the extent to which powerful ministers were at the mercy of court intrigue, and how

China: The antiforeign movement and the second Opium War (Arrow War): …to sign a treaty at Aigun (Aihui), by which the territory on the northern bank of the Amur was ceded to Russia and the land between the Ussuri River and the sea was placed in joint possession by the two countries, pending further disposition. But Beijing refused to ratify the…

South Asian arts: Medieval temple architecture: South Indian style of Karnataka: …and two cave temples at Aihole are early 8th century. Among structural temples built during the rule of the Cālukyas of Bāẖāmi are examples in the North Indian style; but, because the Karnataka region was more receptive to southern influences, there are a large number of examples that are basically…

Yarqon River: …Judaea and Samaria, and the Wadi Ayyalon (Aijalon) in the southeast. In the valley of the latter, according to the Bible, the moon stood still during Joshua’s conquest of the Amorites (Joshua 10).

Aiken, city, seat of Aiken county, western South Carolina, U.S. Aiken lies 16 miles (26 km) northeast of Augusta, Georgia. It was chartered in 1835 and named for the railroad entrepreneur William Aiken. The city was originally a health resort. During the American Civil War the Confederate forces of

Aiken, county, western South Carolina, U.S. It lies in the state’s sandhill region between the North Fork Edisto River to the northeast and the Savannah River border with Georgia to the southwest. The county is also drained by the South Fork Edisto. Aiken and Redcliffe Plantation state parks are

Conrad Aiken, American Pulitzer Prize-winning poet, short-story writer, novelist, and critic whose works, influenced by early psychoanalytic theory, are concerned largely with the human need for self-awareness and a sense of identity. Aiken himself faced considerable trauma in his childhood when he

Conrad Aiken, American Pulitzer Prize-winning poet, short-story writer, novelist, and critic whose works, influenced by early psychoanalytic theory, are concerned largely with the human need for self-awareness and a sense of identity. Aiken himself faced considerable trauma in his childhood when he

Howard Aiken, mathematician who invented the Harvard Mark I, forerunner of the modern electronic digital computer. Aiken did engineering work while he attended the University of Wisconsin, Madison. After completing his doctorate at Harvard University in 1939, he remained there for a short period to

Howard Aiken, mathematician who invented the Harvard Mark I, forerunner of the modern electronic digital computer. Aiken did engineering work while he attended the University of Wisconsin, Madison. After completing his doctorate at Harvard University in 1939, he remained there for a short period to

Joan Aiken, prolific British author of fantasy, adventure, horror, and suspense tales for both juvenile and adult readers. Perhaps best-known as the inventor of a genre called the “unhistorical romance,” Aiken wrote tales that combine humour and action with traditional mythic and fairy tale

Joan Aiken, prolific British author of fantasy, adventure, horror, and suspense tales for both juvenile and adult readers. Perhaps best-known as the inventor of a genre called the “unhistorical romance,” Aiken wrote tales that combine humour and action with traditional mythic and fairy tale

Moms Mabley, American comedian who was one of the most successful black vaudeville performers. She modeled her stage persona largely on her grandmother, who had been a slave. Wise, clever, and often ribald, Mabley dressed in frumpy clothes and used her deep voice and elastic face (and, in later

Aikido, martial art and self-defense system that resembles the fighting methods jujitsu and judo in its use of twisting and throwing techniques and in its aim of turning an attacker’s strength and momentum against himself. Pressure on vital nerve centres is also used. Aikido practitioners train to

Aikido, martial art and self-defense system that resembles the fighting methods jujitsu and judo in its use of twisting and throwing techniques and in its aim of turning an attacker’s strength and momentum against himself. Pressure on vital nerve centres is also used. Aikido practitioners train to

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